I just ran into an odd occurrence. I defined new polytope $p1 by listing its points, and then entered a print command for its facets. I got an incorrect list of 13 facets. Then, I repeated the definition of $p1, and the print command for the facets. This time I got a correct-looking list of 21 facets.

Attached is a text file showing the commands and the printout of facets. Thanks!

Please install a version of polymake on your system, cf. https://polymake.org/doku.php/download/start . The shell.polymake.org version has a number of limitations and is proof-of-concept only. For instance, there is an upper limit on the cpu time. Due to side effects this might also be the reason for the error you reported.